Wooden tubular structure



Dec. 22, 1925- 1,567,022

J. GREEN WOODEN TUBULAR STRUCTURE Filed Nov. 3, 1925 4 Sheets-Sheet 1 Dec. '22, 1 25. 1,567,022

J. GREEN WOODEN TUBULAR STRUCTURE Filed Nov. a, 1925 4 Sheets-Sheet 2 .fiwwzgoigr- XMAA; 0cm

X MMA J 'Dec. 22,1925- J. GREEN WOODEN TUBULAR STRUCTURE Filed Nov. 8, 1925 4 Sheets-Sheet 4 Patented Dec. 22, 1925.

lATEblT JOSHUA GREEN, OF LONDON, ENGLAND.

WOODEN TUBULAR STRUCTURE.

Application filed November 8, 1923.

To all 7072 0m 2 may concern Be it known that I, Josnmx GREEN, a subject of the King of Great. Britain, residing at 61 Leigh Road, Highbury, London, England, hare invented new and useful improvements Relating to lVooden Tubular Structures, of which the following is a specification.

This invention relates to an improved construction of wooden tubular structures and more particularly those whose form varies in diameter in the direction of the length and /or which may have one or more bends, for instance, sound amplifying horns and talking machine tone-arms.

According to the invention I form the whole or part of a tubular structure of varying or un'varying diameter of one or more layers made of a strip or strips of thin wood or veneer wound spirally with the adjacent turns cemented together.

In a suitable way of carrying out the invention I provide a mandrel or former of flexible material, for instance, rubber, of a form corresponding to that of the interior of the structure to be made and upon this former I spirally Wind the strip of thin wood or veneer which may have been previously steamed to increase its pliability. For a structure of unvarying diameter with one or more bonds, the veneer may be cut in the form of a straight strip widened or narrowed, where necessary, in order that the edges of adjacent turns can butt together at the bend or bends.

In building up astruotu-re of unvarying diameter, the strip is wound around the man dr-el, commencing from one end thereof, the butting edges being cemented together and also the butting end edges of the str1ps where more than one is employed in a straight or curved length of structure, or where it is desired to build each straight or curved length separately and afterwards connect them together, in which latter casea flexible mandrel would not be required for each section. A second strip or set of strips may then be wound upon and cemented to those already laid, so as to cover the buttmg joints of the latter and. if required, further layers may be cemented to those already in position to strengthen the structure. The mandrel, after the strips are set, is withdrawn from the structure, the bent portion or portions thereof yielding to enable them Serial No. 873,475.

to be withdrawn from the bend or bends termed in the said structure.

In building up a structure of varying diameter I may make it of spill formation throughout, including bent and flared portions, if any, and is preferably wound on a mandrel of a shape corresponding to that of the structure required, the winding commencing at the smaller end of the said mandrel. The bent portions of a structure of varying diameter, instead of the spill formation, may be formed from a single sheet of material having a series of transverse gores cut out from opposite sides, which latter are bent round and butted or overlapped and cemented together. the spaces from which the gores are cut, closing up and having their edges cemented and butted together.

In a further modification the flaring portion or mouth of the structure, instead of the-spill formation, may be formed of a layer or layers which, or each of which, com prises one or more sheets of veneer having portions cut out so as to produce, when the opposed edges of the resultant openings are butted or overlapped and secured together, the required flared formation.

In a suitable arrangement for carrying out this part of the invention by means of a single sheet of veneer, the openings formed therein extend longitudinally of the flared portion from one end to the other of the latter, small portions or tabs of veneer extend ing beyond the said ends being left to connect the adjoining sections of the mouth together. The sides'of the sections are then butted and connected together and the sides of the sheet also butted and secured together to complete the structure. The tabs may be removed when the structure is built up, or be left intact. or they may be concealed in any suitable way.

For convenience of assembling, the flared structure may be made of a series of sections butted together at their side edges, each section being made from a sheet of veneer having longitudinal openings with tabs at their ends as above described.

To enable the invention to be fully understood I will describe it by reference to the accompanying drawings, in which 2-- Figure 1 is a sectional side view of a tubular structure of unvarying diameter, constructed of a strip of thin wood or veneer wound spirally in accordance with the invention and Figure 2 is a vie-w of a portion of the said strip developed.

Figure 3 is a sectional view of a straight portion of the structure shown in Figure 1 with an additional spiral layer.

Figure l is a side view of a tubular structure of varying diameter throughout its length constituting a sound amplifying horn with a straight stein, also constructed of a strip wound spirally.

Figures 5, 6 and 7 are, respectively, longitudinal sections of portions of the stem, the bend and the flared portion of the said amplifying horn, but drawn to a larger scale than Figure 3 and Figure 8 is a section on the line 88, Figure 5.

Figure 9 is a view of a horn similar to that illustrated in Figure 4., except that the stem is curved.

Figures 10 and 11 are, respectively, an elevation and a plan of another tubular structure of varying diameter constituting a talking machine tone-arm constructed of a strip wound spirally.

Figure 12 is a side view of a portion of a sound amplifying horn, the stem of which is tormed ot a strip wound spirally, whilst the bend and flared portions connected there with are formed differently from the said stem.

Figure 18 is a development of the sheet or veneer from which the bend or elbow of the horn, shown in Figure 12, is made, and

Figure 14 is a development of the sheet or veneer forming a ortion or section of the flared portion of the said horn.

ais the strip or" thin wood or veneer of which I form the whole or part of a tubular structure. whether of unvarying diameter. as illustrated in Figures 1 to 8. or of varying diameter as illustrated in Figures 4t, 9, 10 and 11.

Referrin first to the construction illustr ed in Fi ure 1, the strip a is wound on a flexib e mandrel of the shape of the structure, which is that of a straight tube having a bend at one end, the edges of the adjacent turns or windings abutting and being cemented together. The said strip is of the if orm illustrated in Figure 2, that is to say, the portion wound round the straight part of the mandrel is formed with parallel sides, as indicated at the upper part of the said figure to form the straight portion of the structure, whilst the portion, of the strip wound round the bent part of the mandrel is formed with sides of an undulating or sinuous character, as indicated at the lower part of the said figure, to form the bent part of the said structure. To strengthen the structure. another spiral layer of strip material similar to that described may be applied to the structure so as to cover the cemented joint of the latter, as indicated in Figure 3, which illustrates a portion of the straight part of the structure. ihe mandrel, either before, or after the application of the second layer of strip, may be withdrawn from the structure, its flexibility allowing of th s.

The complete structure, instead of: being formed on a mandrel of: corresponding shape, may be built up in sections on sepa rate maudrels, the sections being afterwards cemented together, the adjacent ends of the strip of any two sections either butting together or slightly overlapping.

Referring now to the amplifying horn i lustrated in Figures 4 to 8, the adjacent spiral turns at the strip a are wound on the mandrel so as to overlap one another, as ind cated clearly in Figures 5 and 8, the overiping portions being cemented together iis construction allows of a strip, or connected strips, of unvarying width, being used tl'iroughout the structure, the amount of: o erlap being equal or unvarying for the stem portion 7, of the horn. but varying where the structure assumes a curved term. For instance, where the tubular structure is bent to form the elbow 0, the spiral turns of the strip a overlap more at the inner part oi the said bend than at the outer portion thereof. as indicated clearly in Figure 6. Where the structure flares to form the mouth (Z of the horn, the overlapping is very pronounced, as indicated clearly in Figure 7, so that the structure, when finished, has a thickened edge, as indicated by the dot and dash lines 6 in the said Figure 7, which edge may be afterwards reduced or thinned. as indicated by the full line f, it. desired, to give a more finished appearance to the horn. 'l'his thinned edge is also shown in Figure 4-. The flared portion (Z can also be thinned as indi'ated by the dotted line 07 either by cutting or by the use of a narrower strip (1 for this part of the structure.

For strena athening purposes, another layer of strip material may be applied to and wound on the exterior of the structure.

In some cases the bend 0 may be dispensed with. the straight stem merging into the flared portion as indicated by the dot and dash lines 6 Figure 4-.

Figure 9 illustrates an amplyitying horn embodying the same overlapping construction as is illustrated in Figures 4 to 8, but showing the horn with a stem curved to the term of an 0'7'93 instead of being straight as indicated in the said latter figure.

lVith reference to the talking machine tone-arm illustrated in Figures 10 and 11, this also embodies the same overlapping construction as that illustrated in Figures 4 to 9 and comprises a straight portion 6 having at its ends right-angle bends or elbows 0, 0 not in the same plane.

The sound amplifying horn illustrated in Figure 12, differs from those described by reference to F igules 4t and 9, with regard to the bend or elbow 0 and the flared portion or mouth (Z, and each of which parts 0 and (Z is formed of thin sheet wood or veneer. Figure 13 is a view of the blank oi thin sheet wood or veneer for the formation oi. the elbow c, the said blank having its ends g and 7t slightly curved convexly and conca ely, respectively, and its sides z', i converging from the end 9 to the end it, transverse gorcs being cut out from the said converging sides so as to leave the side portions of the sheet in the form of a series of oppositely extending lateral ribs j. By bending thcse ribs 7' around the appropriate mandrel they will abut or overlap together at the ends to form the bend or elbow, the abutting edges of the adjacent ribs being cemented together to hold them in position. By making the ribs slightly wider than indicated in Figure 13, they may overlap at their side edges instead of butting together as described.

Another blank similarly formed may be applied and cemented to the said finished elbow for strengthening purposes, and in such av manner that the joints in the said elbow are covered by the ribs of the second blank instead of the joints of both blanks being in register.

Figure it is a view of a portion or sec.- tion or" the thin sheet wood or veneer blank for the formation of the flared portion or mouth (Z of the horn shown in Figure 12, and which blank is of a form similar to that or the blank for the bend or elbow 0, that is to say, its ends k, Zare, respectively, formed convex and concave, whilst its sides m, m converge from the convex end k to the concave end Z. n, n are the longitudinal openings formed in the full length of the blank, the sides of which openings are curved concavely so that when butted togetl'ier the blank will assume the form of a longitudinal section of the flared portion (Z of the horn, so that by using a series of such sections. a complete mouth can be built up, the sides of the sections, which are concavely curved, being butted and cemented together. These butt joints may be covered and reinforced by strips cemented in position; or, if the curved shape of the openings n, n be varied, that is to say, by mak ing them narrower than is required for butting their sides together, it will be understood that such sides can overlap and make a stronger joint than when butted together.

It is to be understood that, instead of making the flared portion cl of the horn in sections as just described, it may be made in one piece.

0, 0, Figure 14, are the tabs or extending portions connecting the sections of the blank together when the longitudinal openings )jlare formed therein, and which tabs, when the flared structure is built up may be removed, if desired. It left intact, the. tabs, 0 may be concealed in any suitable way.

T he three parts of the horn illustrated in Figure 12 viz, the spirally Wound stem Z), and the bend a and flared portion cl made as above described, are then jointed and cemented together by butt joints 7) and To facilitate the construction of tubular structures in accordance with the invention 1 may subject the strip or thin sheet wood or veneer to a steaming process to increase its pliability.

Claims:

1. A tubular structure consisting wholly of non-metallic sheet material in narrow strip form, wound spirally and having its edge portions permanently cemented together.

2. A tubular structure consisting wholly of non-metallic sheet material in narrow strip form wound spirally to form successive layers, the edge portions of the strip material of each layer being permzmently cemented together, said layers being permanently cemented together and the spiral strip material of each exterior layer covering the cemented joint of the layer within the same.

3. A tubular structure consisting wholly 0t non-metallic sheet material in narrow strip term wound spirally and having its edge portions permanently cemented together, and having a continuation in the form of an elbow formed of thin sheet material having transverse gores extending from its lateral edges to near the longitudinal center of the same, and bent so as to bring the edges or" said sheet on opposite sides of the said gores together, said edges and the lateral edges of the sheet being perlnanently cemented together to form an elbow, and said elbow being united to the tubular structure formed by said spirally wound strip material.

4. A tubular structure consisting Wholly of non-metallic sheet material in narrow strip form wound spirally and having its edge portions permanently cemented together, and having a continuation in the form of an elbow formed of thin sheet material having its terminal edges convex and concave respectively, and converging lateral edges extending from the convex edge to the concave edge, said sheet being provided with transversely disposed tapering gores extending inward from said converging edges to near the longitudinal center of said sheet material to form oppositely extending lateral ribs, said sheet material being bent so as to bring the edges of adjacent ribs together and the outer ends of one set of ribs into contact with the outer ends of the other set of ribs, said ribs being permanently cemented together to form an elbow and said elbow being permanently cemented to the tubular structure formed by said spirally wound strip material.

5. A tubular structure consisting wholly of non-metallic sheet material in narrow strip form wound spirally and having its edge portions permanently cemented together, and having a continuation in the form of a flared portion formed oft sheet material provided with an inner concave edge, and an outer convex edge of greater length than the concave edge, and converging lateral edges, said sheet material having longitudinally disposed slits therein increasing in Width from each end of said sheet toward the center, said sheet being bent so as to bring the edges of said slits together and the lateral edges of the sheet together, said edges being permanently cemented, and

said flaring portion being united to the tubular structure formed of said spirally wound strip material.

6. A tubular structure consisting wholly of non-metallic sheet material 1n narrow strip form wound spirallv and having its edge portions permanently cemented together, and having a continuation in the form of an elbow formed of thin sheet material having transverse gores extending from its lateral edges to near the longitudinal center of the same, and bent so as to bring the edges of said sheet on opposite sides of the said gores together, said edges and the lateral edges of the sheet being permanently cemented together to form an elbow, said elbow being united to the tubular structure formed by said spirally wound strip material, and having a continuation in the form of a flaring portion formed of a piece of sheet material having a concave inner edge, a longer convex outer edge, converging lateral edges, and longitudinal slits increasing in width from each end toward their longitudinal center, said sheet being bent so as to bring its lateral edges together and the adjacent edges on opposite sides of said slits together, said edges being permanently cemented together, and said flaring portion being permanently cemented to said elbow portion.

7. A tubular structure having an elbow portion composed of a sheet of non-metallic material having a concave and an opposite convex edge and converging lateral edges, and provided with transversely disposed tapering gores extending from said lateral edges inward toward the longitudinal center of the sheet, said sheet being bent so as to bring the opposite edges oat the gored portions together, and the opposite lateral edges of the sheet together, and said edges being permanently cemented together.

8. A tubular structure having a flared portion consisting of a sheet of non-metallic sheet material provided with an inner concave edge an outer convex edge of greater length than the concave edge and lateral converging edges, said sheet being provided with longitudinal slits increasing in width from each end toward their longitudinal centers, said sheet being bent into tubular form so as to bring the opposite edges of said slits together, and the lateral edges of the sheet together, and said edges being permanently united.

JOSHUA GREEN. 

